Soil and Water Management is a text book intended for students and instructors in University or higher education for Certificate, Diploma and Degree students in a number of courses such as General Agriculture, Agricultural Education and Extension, Horticulture and other allied professions.
The content of the text book has been presented in a coherent format, arranged in an explicit style that adheres to University and higher education curriculum. The textbook is partitioned into section A and section B with Review questions at the end to explicitly help the trainees comprehend the topics. This makes the book suitable for easy reading. For the calculations, worked examples have been solved in a way of illustration and details are presented. Each chapter of the book has worked examples for the readers to expound on subject knowledge.
Table of Content
PART A
SURVEYING IN SOIL AND WATER MANAGEMENT
Introduction to Surveying and Mapping
1.1 Introduction
1.2 Importance of surveying
1.3 Types of surveys
1.4 Basic Error Theory
1.5 Classification of errors
1.6 Mapping in soil and water management
1.7 Methods of Distance Measurement
1.8 Direct Distance Measurement (DDM)
1.9 Obstacles in linear distance measurement
1.10 Slope distance measurement
1.11 Errors in taping
1.12 Optical distance measurement (ODM)
1.13 Electronic Distance Measurement (EDM)
1.14 Worked examples
Chapter 2
Determination of Land Area
2.1 Determination of Land Area
2.2 Methods of estimating area
2.3 Offsets
2.4 Trapezoidal rule
2.5 Simpsons rule
2.6 Other methods of area determination
2.7 Worked example
Chapter 3
Levelling
3.1 Introduction to levelling
3.2 Applications of levelling
3.3 Principles of levelling
3.4 Standard booking sheet
3.5 Plotting the Profile
3.6 Worked examples
Chapter 4
Contours and Contouring
4.1 Contours and Contouring
4.2 Applications of Contours
4.3 Characteristics of Contours
4.4 Methods of Locating Contours
4.5 Land features
4.6 Determination of land slope
Compass Surveying
5.1 Compass Surveying
5.2 Designation of bearings
5.3 Systems of Bearings
5.4 Conversion of bearings
5.5 Fore Bearing (FB) and Back Bearing (BB)
5.6 Local attraction
5.7 Elimination of local attraction
5.8 Traverse Survey
5.9 Procedure for traverse layout
5.10 Types of traverse
5.11 Traverse computation
5.12 Review Questions-Section
PART B
SOIL AND WATER CONSERVATION
Chapter 6
Soil and Water Conservation
6.10 The bottle test procedure for soil texture
Chapter 7
Hydrological Process
Chapter 8
Soil Erosion by Water
8.1 Soil Erosion Process
8.2 Factors affecting erosion by water
8.3 Visual Indicators of Soil Erosion
8.4 Erosion Measurement
8.5 Forms of Erosion
8.6 Erosion by Water
8.7 Water-induced Forms of soil erosion
8.8 The Universal Soil Loss Equation (USLE)
8.9 Worked Examples
8.10 Review Questions
Chapter 9
Erosion by Wind
9.1 Wind erosion process
9.2 Factors affecting wind erosion
9.2.1 Climate
9.2.2, land surface conditions
9.2.3 Soil properties
9.2.4 Land use/cover management
9.3 Forms of wind erosion
9.4 Measurement of wind erosion
9.5 Control of wind erosion
9.6 Wind erosion equation (WEQ)
9.7 Wind erosion models
9.8 Worked examples
9.9 Review questions
Chapter 10
Methods of Controlling Soil Erosion
10.1 Introduction to method of erosion control
10.2 Cultural/biological practices
10.3 Physical Measures
10.4 Terraces
Categories and types of bench terraces
10.5 Cross-sectional area of bench terrace
10.6 Field Terrace design and layout
10.8 Worked Examples
10.9 Review Questions
Objectives and Topics
This textbook aims to provide students and professionals in agricultural and environmental engineering with the theoretical and practical skills necessary for effective soil and water management. It addresses key topics such as survey methodology, mapping, erosion control strategies, and hydrological processes to support sustainable land productivity and food security.
- Fundamentals of land surveying, including distance and area measurement.
- Principles and application of levelling and contouring in agricultural landscape design.
- Understanding soil erosion processes, including both water-induced and wind-driven erosion.
- Advanced techniques for soil and water conservation, specifically focusing on the design and layout of various terrace structures.
- Comprehensive use of mathematical models and empirical formulas for land engineering and runoff estimation.
Auszug aus dem Buch
1.1 Introduction
Soil and water management refers to the application of the practices and operations that help in protection and conservation of soil and water for their enhanced performance and environmental needs. There are some practices and operations that require ‘surveying’ for the purpose of exploring and studying land where soil and water management is required. Thus the need to acquire some knowledge and skills of surveying as applied in soil and water management. The forces behind the soil erosion range from those caused by the main agents of soil erosion to those induced by climate change. To manage the soil and water for improved agricultural production all those forces causing any change should be considered.
Surveying refers to art and science of determining the relative positions of points on, above and below the surface of the earth by means of measurements in three elements of space namely distance, direction and elevation and presentation of this information in graphical or numerical form.
The dimensions of distance and elevation are measured in units of length while that of direction is measured in units of arc. Thus all surveying operations comprise the measurement of distance (horizontal and vertical) and angles. The resulting survey data may lead to computation of areas and volumes.
Summary of Chapters
Introduction to Surveying and Mapping: This chapter defines the core principles of surveying and its critical importance in planning and constructing agricultural and water conservation structures.
Determination of Land Area: This chapter explores various geometrical and practical methods for partitioning land and calculating specific agricultural areas.
Levelling: This chapter details the technical procedures for determining relative elevations and land profiles essential for water flow management.
Contours and Contouring: This chapter explains the definition, characteristics, and practical application of contour lines in mapping land features and determining slopes.
Compass Surveying: This chapter covers the terminology and operational procedures for using compasses in survey line determination and traverse layout.
Soil and Water Conservation: This chapter provides an overview of the history, functions of soil, and the major agents of degradation, emphasizing the necessity of soil-water management engineering.
Hydrological Process: This chapter examines the continuous water cycle and provides methods for estimating peak runoff and rainfall intensity.
Soil Erosion by Water: This chapter analyzes the processes of detachment, transport, and deposition, while introducing the Universal Soil Loss Equation (USLE).
Erosion by Wind: This chapter covers the physics of wind erosion, including transportation types like saltation and suspension, and strategies for mitigation.
Methods of Controlling Soil Erosion: This chapter focuses on practical and engineering interventions, specifically providing detailed guidance on the design and construction of various terrace systems.
Keywords
Soil and Water Management, Surveying, Land Area Determination, Levelling, Contouring, Compass Surveying, Soil Erosion, Water Conservation, Hydrology, USLE, Wind Erosion, Terracing, Runoff, Catchment, Agricultural Engineering.
Frequently Asked Questions
What is the core focus of this publication?
The work provides a comprehensive textbook for students and field officers on the theoretical and practical application of surveying, soil erosion control, and water management in agricultural environments.
What are the primary thematic areas covered?
The book is divided into two sections: Part A, covering foundational surveying techniques like levelling and mapping; and Part B, focusing on soil and water conservation, erosion mechanics, and engineering design of control structures.
What is the primary objective or research question addressed?
The primary objective is to equip learners with the necessary mathematical and engineering skills to manage land resources efficiently, prevent soil degradation, and improve food security.
Which scientific methods are utilized in this work?
The book employs engineering surveying techniques, empirical formulas for soil loss (like the USLE), statistical hydrological analysis, and geometric calculations for area and volume estimation.
What topics are discussed in the main body of the text?
The text treats diverse topics including linear distance measurement, tape corrections, contouring strategies, wind erosion physics, hydrological cycle components, and the design of physical structures like check dams and terraces.
Which keywords define this work?
Key terms include soil management, surveying, levelling, USLE, terrace design, catchment runoff, and erosion control.
How is the "bottle test" used in field assessments?
The bottle test is described as a simple field procedure to determine soil texture classes by observing the settling layers of sand, silt, and clay in a transparent container filled with water.
What is the importance of the Universal Soil Loss Equation (USLE)?
The USLE is presented as a vital tool to estimate potential annual soil loss from a catchment based on six composite factors, allowing conservationists to predict erosion rates and design more intensive conservation practices.
- Quote paper
- Dr Raphael Muli Wambua (Author), 2020, Soil and Water Management. An Introductory Textbook, Munich, GRIN Verlag, https://www.grin.com/document/920144
